Functions of a portable terminal such as a smartphone and a tablet PC (personal computer) have been extremely advanced, which leads to large power consumption.
Therefore, it is demanded that charging can be performed everywhere including an inside of a vehicle. As a trend in recent years, a portable terminal charging device capable of performing so-called wireless charging without using a cable has attracted attention. According to the wireless charging device, when a portable terminal is placed on a placement portion of an object to be charged, the portable terminal can be charged with magnetic flux from a charging coil.
PTL 1 discloses an example of such a wireless charging device. The charging device disclosed in PTL 1 employs a coil array system. In the system, among a plurality of charging coils constituting a coil array, only a part of charging coils corresponding to a position on which a portable terminal is placed (exactly, a position of a power receiving coil incorporated in the portable terminal) is used for charging.